In general, since a scooter having two rear wheels has stability such that the scooter does not easily fall down to a left or right side in comparison with a bicycle or a two-wheeled scooter, anyone can easily run and ride the scooter. In addition, since a relatively wide carrier section can be provided on an upper section of a rear wheel section, the scooter can be used as an inexpensive means of transportation.
However, since both of the real wheels of such a scooter protrude outward more than a front wheel, the scooter may be more easily turned over than the bicycle or the two-wheeled scooter.
That is, when a driver changes a direction while running or the scooter runs over an obstacle on a road, the three-wheeled scooter may be tilted in a direction in which a centripetal force is applied, and the scooter may not be able to maintain or rapidly return to an equilibrium state of the rear wheel section.
Accordingly, scooters have not been popularized as an inexpensive means of transportation that not only ordinary persons, but also the old and the infirm can easily learn to ride due to the above-mentioned problems.
Accordingly, improvements of forward movement stability and recovery speed of when a center of gravity has moved are urgently required such that drivers can easily drive and stably ride scooters regardless of a running speed of the three-wheeled scooter, a load on the rear wheel section, a road surface state, and so on.